Current state-of-the art postal address processing normally acquires address information appearing on mail pieces in electronically captured binary form. This information is then used by automated mail sorting equipment and processing systems to sort the mail based upon the captured destination information. In these systems, scanners of various types are used to capture an image of one or more surfaces of a mail piece. The image is then analyzed using automated or human-aided systems such as optical character recognition (OCR), a bar code reader (BCR), specialized video processing systems, image processing systems, forms readers, forms video processing, and video coding systems. Allen et al. U.S. Pat. No. 5,422,821 describes one such system wherein mail piece addresses and bar codes are scanned and checked against a forwarding address database so that forwarding to the new address can occur without first sending the mail piece to the old address. Other systems only use bar code readers, acquiring destination information from bar codes previously applied to the mail pieces.
U.S. Pat. No. 5,311,999 describes a tunnel scanner for packages wherein image data for different sides of the parcel is taken in a rough scan, and then a fine scan is made of one of the sides based on operator recognition of a split screen display of all the scanned images, e.g., the one with the writing on it is chosen. The operator, using a touch screen, mouse or similar device, chooses the partial image. In an alternative automated embodiment, six images obtained from the rough scan are examined for regions, which coincide in a selection of features with the model of an address sticker, or an address region on a package. Features of this type are, for example, the color contrast of an area compared to its surroundings, the gray value contrast of an area compared to its surroundings, the shape of this area, the type and number of dark regions within the area, its location with respect to other distinct objects and with respect to the outline of the package.
According to known image recognition methods, the image most likely containing an address region is selected automatically from the images obtained by rough scanning, whereupon this region is subjected to fine scanning. The images may also already be supplied to an automatic character recognition device. Fine scan processing then takes place only if the images obtained by rough scanning are selected by the region of interest selection device. Rough scanning may be also be done by extracting a down sampled rough image from a fine (high resolution) scan.
Conventional scanning methods rely on a number of techniques for identifying and decoding possible regions of interest on a scanned mail piece. According to one such system, the overall image is subdivided into a 3-by-3 array of nine areas. Each area has a predetermined probability associated with it that any written matter found within the area will be an address. The center area may be assigned the highest probability. Current software also checks written matter in each region to determine whether it forms lines, is text justified, uses a single (common) font, and whether the matter is a bar code. All of these factors are considered in determining whether an address or other specific type of identification has been found. For purposes of performing several different kinds of analysis (e.g., OCR) simultaneously, it is preferred to send the initial scan results to more than one computer or processor.
Scanning systems of the kind used to read mail can also be used to read forms, such as postal change of address forms. According to current United States Postal Service (USPS) procedures, a person wishing to have the USPS forward mail to a new address submits a Change of Address (COA) Order Form (Form 3575) that requests mail forwarding. This form is normally completed by hand-printing the requested information including name, old address, new address, whether the move is for a family or individual, effective date and duration of the change on the form and submitting the form to a local post office. Commonly-assigned U.S. patent application Ser. No. 09/534,182, filed Mar. 24, 2000, the contents of which are hereby incorporated by reference herein for all purposes, provides a process for handling such forms wherein it is necessary to transmit the image from the computer associated with the scanner to a second computer which is used to analyze (decode) the image. The images are generally transmitted through a network or other data communication line.
For purposes of both mail pieces and form processing, the read rate of the scanning system should be as high as possible. Systems such as MLOCR (multiline optical character readers) and bar code scanners are incorporated into postal sorting machines now in use such as DIOSS (delivery bar code sorter/optical character reader/input subsystem/output subsystem) machines and DBCS (delivery bar code sorter) machines. These systems achieve read rates as high as 80%. However, the unreadable mail must be diverted and sent to video coding, where a human operator reviews an image of the mail piece and keys in the corrected address so that the corresponding zip+4 postal bar code can be printed on the mail piece. This manual review process is laborious and expensive, and it has been estimated that a 1% improvement in read rate corresponds to a savings of 9.5 million dollars per day. The present invention provides a system and method that can significantly improve the OCR and bar code scanning success rate in postal operations and potentially in other environments.